Thick tempered martensitic steel plates were friction stir processed at different tool traverse and rotational speeds. Friction stir processing led to formation of finer martensite phase, ferrite, and higher angle grain boundaries, which resulted in higher hardness of the processed samples. However, the macro mechanical results indicated that the tensile strength and elongation were reduced after friction stir processing, was due to the formation of ferritic bands and WC debris in the processed zones. The brittle fractured surfaces of processed samples confirmed the negative effect of friction stir processing on tensile behavior, which contained more cleavage than dimples compared to base material. The outcome of this study can be used for surface modification of thick martensitic materials for industrial applications.

在不同的刀具横向和转速下对厚回火马氏体钢板进行搅拌摩擦加工。搅拌摩擦加工导致形成更细的马氏体相、铁素体和更大角度的晶界，这导致加工样品的硬度更高。然而，宏观力学结果表明，搅拌摩擦加工后拉伸强度和伸长率降低，这是由于加工区形成了铁素体带和WC碎片。加工样品的脆性断裂表面证实了搅拌摩擦加工对拉伸行为的负面影响，与基材相比，其包含比凹坑更多的解理。这项研究的结果可用于工业应用中厚马氏体材料的表面改性。